## Non-ideal bit commitment and coin tossing

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Can someone please explain rigorously the reasoning behing non-ideal ($$\epsilon$$-concealing and $$\delta$$-binding) bit commitment scheme and the impossibility of coin tossing.

What is bias in coin tossing? How to use non-ideal bit commitment scheme to come up with non-ideal coin tossing and how to estimate the bias.

Lo-Chau paper "Why quantum bit commitment and ideal coin tossing are impossible" has some of the details, but it looks like it omits a lot of details we could add 22 years later.

And I could not understand Mayers' work "Trouble with quantum bit commitment".

Thank you very much.

The $$\epsilon$$-concealing and $$\delta$$-binding parameters in the bit commitment scheme merely interpolate between the two mentioned extremes, ultimately there is a fundamental trade off between the two parameters, which demonstrates that there is no ideal bit commitment scheme.